git-mergetool--lib.sh

   1 #!/bin/sh
   2 # git-mergetool--lib is a library for common merge tool functions
   3 diff_mode() {
   4         test "$TOOL_MODE" = diff
   5 }
   6
   7 merge_mode() {
   8         test "$TOOL_MODE" = merge
   9 }
  10
  11 translate_merge_tool_path () {
  12         echo "$1"
  13 }
  14
  15 check_unchanged () {
  16         if test "$MERGED" -nt "$BACKUP"
  17         then
  18                 status=0
  19         else
  20                 while true
  21                 do
  22                         echo "$MERGED seems unchanged."
  23                         printf "Was the merge successful? [y/n] "
  24                         read answer || return 1
  25                         case "$answer" in
  26                         y*|Y*) status=0; break ;;
  27                         n*|N*) status=1; break ;;
  28                         esac
  29                 done
  30         fi
  31 }
  32
  33 valid_tool_config () {
  34         if test -n "$(get_merge_tool_cmd "$1")"
  35         then
  36                 return 0
  37         else
  38                 return 1
  39         fi
  40 }
  41
  42 valid_tool () {
  43         setup_tool "$1" || valid_tool_config "$1"
  44 }
  45
  46 setup_tool () {
  47         case "$1" in
  48         vim*|gvim*)
  49                 tool=vim
  50                 ;;
  51         *)
  52                 tool="$1"
  53                 ;;
  54         esac
  55         mergetools="$(git --exec-path)/mergetools"
  56
  57         # Load the default definitions
  58         . "$mergetools/defaults"
  59         if ! test -f "$mergetools/$tool"
  60         then
  61                 return 1
  62         fi
  63
  64         # Load the redefined functions
  65         . "$mergetools/$tool"
  66
  67         if merge_mode && ! can_merge
  68         then
  69                 echo "error: '$tool' can not be used to resolve merges" >&2
  70                 exit 1
  71         elif diff_mode && ! can_diff
  72         then
  73                 echo "error: '$tool' can only be used to resolve merges" >&2
  74                 exit 1
  75         fi
  76         return 0
  77 }
  78
  79 get_merge_tool_cmd () {
  80         # Prints the custom command for a merge tool
  81         merge_tool="$1"
  82         if diff_mode
  83         then
  84                 echo "$(git config difftool.$merge_tool.cmd ||
  85                         git config mergetool.$merge_tool.cmd)"
  86         else
  87                 echo "$(git config mergetool.$merge_tool.cmd)"
  88         fi
  89 }
  90
  91 # Entry point for running tools
  92 run_merge_tool () {
  93         # If GIT_PREFIX is empty then we cannot use it in tools
  94         # that expect to be able to chdir() to its value.
  95         GIT_PREFIX=${GIT_PREFIX:-.}
  96         export GIT_PREFIX
  97
  98         merge_tool_path="$(get_merge_tool_path "$1")" || exit
  99         base_present="$2"
 100         status=0
 101
 102         # Bring tool-specific functions into scope
 103         setup_tool "$1"
 104
 105         if merge_mode
 106         then
 107                 merge_cmd "$1"
 108         else
 109                 diff_cmd "$1"
 110         fi
 111         return $status
 112 }
 113
 114 list_merge_tool_candidates () {
 115         if merge_mode
 116         then
 117                 tools="tortoisemerge"
 118         else
 119                 tools="kompare"
 120         fi
 121         if test -n "$DISPLAY"
 122         then
 123                 if test -n "$GNOME_DESKTOP_SESSION_ID"
 124                 then
 125                         tools="meld opendiff kdiff3 tkdiff xxdiff $tools"
 126                 else
 127                         tools="opendiff kdiff3 tkdiff xxdiff meld $tools"
 128                 fi
 129                 tools="$tools gvimdiff diffuse ecmerge p4merge araxis bc3"
 130         fi
 131         case "${VISUAL:-$EDITOR}" in
 132         *vim*)
 133                 tools="$tools vimdiff emerge"
 134                 ;;
 135         *)
 136                 tools="$tools emerge vimdiff"
 137                 ;;
 138         esac
 139 }
 140
 141 guess_merge_tool () {
 142         list_merge_tool_candidates
 143         echo >&2 "merge tool candidates: $tools"
 144
 145         # Loop over each candidate and stop when a valid merge tool is found.
 146         for i in $tools
 147         do
 148                 merge_tool_path="$(translate_merge_tool_path "$i")"
 149                 if type "$merge_tool_path" >/dev/null 2>&1
 150                 then
 151                         echo "$i"
 152                         return 0
 153                 fi
 154         done
 155
 156         echo >&2 "No known merge resolution program available."
 157         return 1
 158 }
 159
 160 get_configured_merge_tool () {
 161         # Diff mode first tries diff.tool and falls back to merge.tool.
 162         # Merge mode only checks merge.tool
 163         if diff_mode
 164         then
 165                 merge_tool=$(git config diff.tool || git config merge.tool)
 166         else
 167                 merge_tool=$(git config merge.tool)
 168         fi
 169         if test -n "$merge_tool" && ! valid_tool "$merge_tool"
 170         then
 171                 echo >&2 "git config option $TOOL_MODE.tool set to unknown tool: $merge_tool"
 172                 echo >&2 "Resetting to default..."
 173                 return 1
 174         fi
 175         echo "$merge_tool"
 176 }
 177
 178 get_merge_tool_path () {
 179         # A merge tool has been set, so verify that it's valid.
 180         merge_tool="$1"
 181         if ! valid_tool "$merge_tool"
 182         then
 183                 echo >&2 "Unknown merge tool $merge_tool"
 184                 exit 1
 185         fi
 186         if diff_mode
 187         then
 188                 merge_tool_path=$(git config difftool."$merge_tool".path ||
 189                                   git config mergetool."$merge_tool".path)
 190         else
 191                 merge_tool_path=$(git config mergetool."$merge_tool".path)
 192         fi
 193         if test -z "$merge_tool_path"
 194         then
 195                 merge_tool_path="$(translate_merge_tool_path "$merge_tool")"
 196         fi
 197         if test -z "$(get_merge_tool_cmd "$merge_tool")" &&
 198                 ! type "$merge_tool_path" >/dev/null 2>&1
 199         then
 200                 echo >&2 "The $TOOL_MODE tool $merge_tool is not available as"\
 201                          "'$merge_tool_path'"
 202                 exit 1
 203         fi
 204         echo "$merge_tool_path"
 205 }
 206
 207 get_merge_tool () {
 208         # Check if a merge tool has been configured
 209         merge_tool="$(get_configured_merge_tool)"
 210         # Try to guess an appropriate merge tool if no tool has been set.
 211         if test -z "$merge_tool"
 212         then
 213                 merge_tool="$(guess_merge_tool)" || exit
 214         fi
 215         echo "$merge_tool"
 216 }